中南大学学报（自然科学版）2018，Vol.49Issue(1)：55-63,9.DOI:10.11817/j.issn.1672-7207.2018.01.008
单 β 相镁锂合金Mg-11Li-3Al-0.4Y中温拉伸行为
Tensile behavior of β-phase Mg-11Li-3Al-0.4Y alloy at medium temperature
摘要
Abstract
New β-phase Mg-11Li-3Al-0.4Y alloy sheet with thickness of 1 mm was prepared by casting, hot-rolling and annealing processes. The fracture morphology and mechanical properties were investigated with scanning electron microscope and medium-temperature stretch test machine, respectively. Additionally, constitutive equation including flow stress, strain rate and deformation temperature was established by hyperbolic sine model with Zene-Hollomon parameter. The results show that the flow stress decreases with the increase of deformation temperature and reduction of strain rate. A pronounced post-relaxation effect followed by a serrated flow curve is shown in true stress-strain curves with low strain rate, which is also called the Portevin-Le Chatelier effect, and it is the first time that Portevin-Le Chatelier effect appears in β-phase Mg-Li-Al alloy. Cleavage fracture is replaced by dimple fracture with the increase of deformation temperature, according to the observation of electron microscope.关键词
Mg-11Li-3Al-0.4Y合金/热变形/Portevin-LeChatelier效应/动态再结晶/本构方程Key words
Mg-11Li-3Al-0.4Y alloy/thermal deformation/Portevin-Le Chatelier effect/dynamic recrystallization/constitutive equation分类
矿业与冶金引用本文复制引用
丁洪波,周海涛,秦径为,李夏雷,刘克明..单 β 相镁锂合金Mg-11Li-3Al-0.4Y中温拉伸行为[J].中南大学学报（自然科学版）,2018,49(1):55-63,9.基金项目
国家自然科学基金资助项目(51461018) （51461018）
江西省自然科学基金重点资助项目(20133BAB20008) (Project(51461018) supported by the National Natural Science Foundation of China （20133BAB20008）
Project(20133BAB20008) supported by the Key Program of Natural Science Foundation of Jiangxi Province) （20133BAB20008）
